Duty Cycle - Honeywell Kromschroder TZI Series Technical Information

Project planning information

5 . 7 Duty cycle

The duty cycle indicates for how long the ignition trans-
former can be switched on within 180 s, without it be-
ing overloaded.
100
80
60
40
20
0
-20
For ignition transformers, the duty cycle is dependent
on the ambient temperature.
TZI/TGI duty cycle in % – see page 13 (Technical
data).
Converting the duty cycle into seconds:
Duty cycle [%] × 180 s
Duty cycle [s] =
TZI, TGI · Edition 06.16
0 20 40 60
Ambient temperature [°C]
100%
Example
Ignition transformer TZI 7-25/20W with a duty cycle of
20% for an ambient temperature of -20 to +35°C.
20 [%] × 180 s
Duty cycle =
100%
In an ambient temperature of -20 to +35°C, this results
in a maximum duty cycle of 36 s within 180 s for the
ignition transformer.
For an automatic burner control unit with an ignition
time t = 6 s, for example, the resultant timing cycle is a
Z
maximum of 2 ignitions per minute.
0 60
Legend
t = 6 s
Z
= 36 s
120 180
t [s]
11